RT Journal Article SR Electronic JF Heart JO Heart FD BMJ Publishing Group Ltd and British Cardiovascular Society SP 937 OP 938 VO 95 IS 11 A1 J Davies A1 K H Parker A1 D P Francis A1 A D Hughes A1 J Mayet YR 2009 UL http://heart.bmj.com/content/95/11/937.2.abstract AB